Characterization of New Wheat-Dasypyrum breviaristatum Introgression Lines with Superior Gene(s) for Spike Length and Stripe Rust Resistance

Dasypyrum breviaristatum (genome VbVb) contains potentially important traits for commercial wheat production. Chromosome 2Vb of D. breviaristatum carries several desirable agronomic characters, including long spike length as well as enhanced resistance to stripe rust, which are expressed in a common wheat background. In this study, wheat-D. breviaristatum 2Vb deletion lines were produced and identified by fluorescence in situ hybridization (FISH), and 74 molecular markers specific to D. breviaristatum chromosome 2Vb were physically localized in 4 distinct chromosomal regions. New wheat-D. breviaristatum 2Vb translocation lines were also characterized by FISH. The breakpoint of the translocation T3AS.3AL-2VbS was determined by physically mapped molecular markers. Field evaluation revealed that genes affecting plant height and spike length are located on fraction length (FL) 0.65-1.00 of 2VbS, while the stripe rust resistance gene(s) are located on FL 0.40-1.00 of D. breviaristatum chromosome 2VbL. The newly characterized wheat-Dasypyrum chromosomal introgressions are of potential value for the improvement of the yield and disease resistance of wheat.

MITIGATION OF SLIVERS USING A NEW PROPELLANT GRAIN DESIGN TO IMPROVE PROPULSION SYSTEMS

The research work addresses mathematical modelling and computational analysis of novel solid propellant grain configuration. The aviation industry is working on propulsion systems as well. For high thrust in rockets, space ships, and even in aircraft, solid propellant grains can be used as fuel. Grain design is a vital and integral part of solid propellant design. The designer has many options available for selecting grain configuration. Several design parameters – volumetric loading fractions, web fraction, length to diameter ratio, and port area – are normally tailored to mission demands. The star grain configuration has been a mainstay in this industry since 1935. The star grain configuration does however have a long-standing drawback, namely the formation of slivers. In this paper we present a new grain configuration, the “rose petal”, which overcomes the drawback of the traditional star grain design. The configuration is modelled using relevant internal ballistic relations. The design computation is executed in MATLAB. Thrust and time and burn area time curves are generated for a prescribed port area. Comparisons are drawn between the two configurations, clearly revealing that the new configuration obviates the occurrence of unwanted slivers otherwise generated in the old star design, which lowers the efficiency of all those propulsion systems in which solid propellants are used.

Open Loop Stability on Hybrid Synchronous Motor

This paper searched open loop stability on hybrid synchronous motor which is made of a permanent magnet part and a reluctance part, there is important influence for the ratio k, the fraction length of the permanent magnet part, and the displaced angle α, the between the two part d-axis, the small-signal mathematics model was derived based on d-q reference frame, and optimized the appropriate k and α value considering the stability and the harmonic distortion factor (THD), The simulation results show that the model is correct.

Design of New Type Synchronous Motor Based on the Stability

New type synchronous motor is made of a permanent magnet part and a reluctance part, there are import influence for the motor performance by the variable k, the fraction length of the permanent magnet part, and α, the displaced angle between the two part d-axis. The math model is derived based on Lyapunov stability, searching the appropriate k and α value, plotting stability regions, giving the simulation results. The calculation results are verified by simulation results.

A Microstructure-Level Material Model for Simulating the Machining of Carbon Nanotube Reinforced Polymer Composites

A continuum-based microstructure-level material model for simulation of polycarbonate carbon nanotube (CNT) composite machining has been developed wherein polycarbonate and CNT phases are modeled separately. A parametrization scheme is developed to characterize the microstructure of composites having different loadings of carbon nanotubes. The Mulliken and Boyce constitutive model [2006, “Mechanics of the Rate Dependent Elastic Plastic Deformation of Glassy Polymers from Low to High Strair Rates,” Int. J. Solids Struct., 43(5), pp. 1331–1356] for polycarbonate has been modified and implemented to capture thermal effects. The CNT phase is modeled as a linear elastic material. Dynamic mechanical analyzer tests are conducted on the polycarbonate phase to capture the changes in material behavior with temperature and strain rate. Compression tests are performed over a wide range of strain rates for model validation. The model predictions for yield stress are seen to be within 10% of the experimental results for all the materials tested. The model is used to study the effect of weight fraction, length, and orientation of CNTs on the mechanical behavior of the composites.

Topography of Capillary Density, Glucose Metabolism, and Microvascular Function within the Rat Inferior Colliculus

A midbrain nucleus of the auditory system, the inferior colliculus, was used as a model for analyzing spatial correlations or “coupling” among capillary density, tissue glucose metabolism, and several measures of microvascular function in the rat. The capillary bed of the inferior colliculus was examined with stereological techniques, and physiological measures were obtained with radioactive tracers, quantitative autoradiography, and image processing. Within the colliculus, capillary density, volume fraction, length, and surface area were highest in the central nucleus where the packing densities of neuropil and perikarya are greatest. Rates of glucose metabolism and blood flow correlated closely with capillary density in a 3 × 2 matrix of collicular subregions in the sagittal and coronal planes. The strength of this correlation suggests that estimates of capillary density can be made from measurements of tissue glucose metabolism within this structure under normal conditions. Microvascular blood volume and transcapillary flux of a neutral amino acid, α-aminoisobutyric acid, were homogeneous throughout the colliculus. The studies demonstrate quantitatively in a single brain nucleus a close correspondence between cytoarchitecture, richness of the capillary bed, and complexity of neural activity (inferred from local measures of glucose metabolism and blood flow). Such relationships were suggested by Craigie 67 years ago.